The importance of diastereo- and enantioselective aldehyde allylation and crotylation is demonstrated by the direct relevance to the products of these reactions to important classes of natural products and other compounds of biological relevance. While stereoselective aldehyde allylation and crotylation methods have been developed, many suffer from drawbacks related to practical liabilities such as low temperature metallation procedures, multiple steps in carrying out the reactions and complex work-up procedures. Additionally, the practicability of such methods has been limited, due to requirements of low temperature metallation and in situ generation of the reagent.